Field of the Invention
The present invention relates to a display device, and more particularly, to a display device with integrated touch screen.
Discussion of the Related Art
Touch screens are a type of input device that is included in image display devices such as liquid crystal displays (LCDs), Field Emission Displays (FEDs), plasma display panels (PDPs), electroluminescent displays (ELDs), and electrophoretic displays (EPDs), and allows a user to input predetermined information by applying a pressure (i.e., pressing or touching) to a touch sensor of a touch screen while looking at the image display device.
Particularly, the demand of display devices with integrated in-cell type touch screen, which include a plurality of built-in elements configuring the touch screen for slimming portable terminals such as smart phones and tablet Personal Computers (PCs), is recently increasing.
General display devices with integrated in-cell type touch screen transfer touch data to a system once for each one vertical sync signal (Vsync) that defines one frame period. Hereinafter, driving of a related art display device with integrated in-cell type touch screen will be described with reference to FIG. 1.
FIG. 1 is a timing chart showing signals during a display period and a touch sensing period based on one vertical sync signal, in a general display device with integrated touch screen.
In the general display device with integrated self-capacitive and in-cell type touch screen, as shown in FIG. 1, the display period and the touch sensing period are time-divided and driven according to the sync signal during one frame.
For example, a plurality of electrodes receive a common voltage to perform a display driving operation in the display period in units of a frame, and in the touch sensing period, the plurality of electrodes receive a touch sensing signal to perform a touch driving operation.
When the general display device with integrated touch screen is a high-resolution display device, the number of data to input increases in the display driving operation, and for this reason, time for the display driving operation also increases. On the other hand, time for the touch driving operation is insufficient.